Topic 2: Organisation of the Organism

Revision flashcards covering cell structure, functions of organelles, bacterial cells, specialised cells, levels of organisation, and magnification from Cambridge IGCSE Biology 0610 Topic 2.

Structures shared by animal and plant cells

Cell membrane, cytoplasm, nucleus, ribosomes, and mitochondria.

Plant-only cell structures

Cellulose cell wall, chloroplasts, and a large permanent vacuole.

Plant vacuole

A permanent structure that stores cell sap and maintains cell shape.

Animal cell vacuoles

Small structures occurring only as small vesicles.

Cell membrane

A partially permeable barrier that controls what enters and leaves the cell.

Cell wall

A fully permeable outer layer made of cellulose that stops plant cells from bursting.

Cytoplasm

A watery jelly where metabolic reactions take place.

Nucleus

An organelle containing chromosomes of DNA that controls the proteins made.

Chloroplasts

Structures containing chlorophyll that serve as the site of photosynthesis.

Mitochondria

Organelles responsible for aerobic respiration; cells requiring more energy contain more of them.

Ribosomes

Cellular structures responsible for protein synthesis.

Bacterial cell wall

An outer protective structure found in bacteria that is not made of cellulose.

Circular DNA

The creditable phrase for the genetic material that floats free in the cytoplasm of a bacterial cell.

Plasmids

Small extra circles of DNA found in bacterial cells.

Organelles present in bacteria cells

Cell wall not cellulose, membrane, cytoplasm, ribosome

Organelles absent in bacterial cells

Nucleus, mitochondria, and chloroplasts.

Ciliated cells

Specialised cells that move mucus in the trachea and bronchi.

Root hair cells

Long, thin specialised cells with a large surface area for absorption, containing no chloroplasts.

Palisade cells

Specialised plant cells adapted for photosynthesis.

Neurones

Specialised cells adapted to conduct electrical impulses.

Red blood cells

Specialised cells packed with haemoglobin and lacking a nucleus, adapted to transport oxygen.

Gametes

Sperm and egg cells specialised for reproduction.

Tissue

A group of similar cells working together to perform the same function, such as stomach lining.

Organ

A group of different tissues working together, such as the stomach, heart, or leaf.

Organ system

A group of organs with related functions, such as the digestive system.

Magnification formula

$\text{magnification} = \frac{\text{image size}}{\text{actual size}}$ (has no units; written with a $\times$).

Millimetre to micrometre conversion

$1\,\text{mm} = 1000\,\mu\text{m}$ (convert units before calculating magnification).